B
　　book ——> reserve
　　boring ——> uninteresting
　　borrow —— > lend
　　breathe —— > air pollution
　　brighten one's spirits —— > make one feel better
　　broke —— > no money
　　budget —— > money // price
　　bump into —— > meet // see
　　buy —— > purchased
　　by and by —— > in a short while
　　by leaps and bounds —— > quickly